Definition
Mars is a rocky planetary body surrounded by a highly reduced atmospheric envelope. Its solid surface, ice layers and dust constitute a system where mineral substrate, seasonal frost and atmospheric motion interact.
Internal structure
The interior consists of a partially fluid metallic core, a silicate mantle with viscoelastic behavior, and a relatively thick crust. Transitions between these regions appear as variations in rigidity, density and thermal conductivity, shaping slow deformations and internal gradients.
Surface and landforms
The surface displays vast plains, fractured highlands, extensive volcanic provinces and impact basins. Surface materials alternate between altered rocks, basaltic deposits, fine-grained sediments and dust cover lifted by the atmosphere.
Fluid envelopes
The very clear atmosphere is composed mainly of carbon-rich gases and suspended dust. Its low density limits heat transport, cloud formation and near-surface circulation. Seasonal cycles regulate the condensation and sublimation of ice near the poles, redistributing fine dust.
Evolution and interactions
Interactions between the cooling interior, surface ice and atmospheric flows drive a slow evolution. Orbital variations influence glacial deposits, dust migration and the stability of ground ice. Geomorphological traces reveal past liquid flows now restricted to very localized phenomena.
Constraints and environmental conditions
Low pressure, extreme dryness and large thermal amplitude limit fluid processes at the surface. The absence of a global magnetic field reduces protection against energetic particles, gradually altering the upper atmosphere and the state of exposed materials.